Intercommunication system



July 18, 1950 w. E. wADswoRTH 2,515,432

` INTERcoMMUNIcATIoN sYsT'EM Filed July 8, 1948 2 Sheets-Sheet 1 I 'l LSBE'ETETPB 4 J SCW I cB5-=- TE SC @I ZIUVVENTOR.

Sue-STA'HQN 1 I J BY FIE. I MQQM flrroRNE-Ya July 18, 1950 w. E. wADswoRTH INTERcoMMUNIcATIoN SYSTEM 2 Sheets-Sheet 2 Filed July 8, 1948 INVENTOR.

TToR/vsvs FIG. 2

Patented July 18, 1950 UNITED omcsf" INTERCJOMMUNICATION SYSTEM William E. Wadsworth, YTampa', vFla. Application July s, 1948, serial No. 37,547y

1 The invention relates to inter-communication systems, and more particularly those of the Vtype having a remote controlled loud speaker.

The object of the invention is to provide a system of the character above described in which any substation can talk directly to any other substation.

A further object of the'invention is to provide an intercommunication system that requiresonly one control mechanism and amplifying station which may be placed in any desired location and may be sealed against tampering. Each substation is provided with a loud speaker and a set of control buttons electrically connected with the control'and amplifying station which includes all the relays used in the system. One control button per substation controls both talking Iand listening with another substation. One control button is provided Vat each substation to release or clear the system. Thecalled partly simply answers from where he hears the* call vanddoes not have to go to :a box, push a button or lever, before he can answer, thus saving time and objectionable inconveniences. f

The invention further consists in the several features hereinafter set forth and more particularly defined by claims at the conclusion here In the drawings:

Fig. 1 is a diagrammatic view showing the substations and their Wiring;

Fig. 2 is a -diagrammatic view ofV the vcontrol and amplifying station with its Wiring which connects up with the substations of Fig. 1.

Referring to the drawings, I have shown flve substations designated I, 2, 3, 4, and 5, respectively. Each substation has a loud speakers, one of whose terminals is connected by a conductor 6 to ground and the other of. whose terminals for the different stations a re connected, respectively, by the sound wires IA, 2A, 3A, 4A, and EA.

Each substation has four call buttons or circuit closures and one release button or circuit closure RB and a signal light BL. The Icall buttons for station I are 4designated at CBZ, C B3, CBII, and CB5. The call buttons for station 2 are CBI CB3, CBII, and CBS. The call buttons for station 3 are CBI, CBZ, CBlI, and CBS. 'The call buttons for station 4 are CBI CBZ, CB3`, and CBS. The call buttons for station 5 are CBI,` CB 2, CB3, and CBII. The call buttons for station Al have a common return conductor IB, those offlstation 2 a return conductor ZB, 'those of station 3 areturn conductor 3B, those of station 4 a return conductor IIB, and thoseof station 5` a commonreturn conductor 5B. There are five call button conductors IC,- 2C, 3C, 4 C, and 5G. The call buttons at each station are connected fto these call button conductors, all of the call buttons CBI being connected to conductor IC,' al1 s claims; (ol. rvs- 37) .eratingf coil. I I.

withthe contact H.

of the call buttons CB2 being connected tofonductor 2C,.al1 of theV call buttons CB3,, being connectedto conductor 3C, allof the Vcall buttons CBII being connectedto conductor 4G, 'and allflof the call lbuttons CB5 being connected tqconductor 5C'. M V, One terminal of the release buttons RB',. for,the different stations is connected, respectively,/by Conductors RI, R2, R3, RII, and RE, respectively, to ,a busy .and release. wire or conductor RBW, and the other terminalwof these release' buttons is ,connected byaconductor 1 to its ground conductor,6. A signal orbusy light BL .for each station is connected across the conducto'r' Grand theconductor connectingthe release buttonfof this 'station with the busy and release wire RBW.

Thesoundvwires or conductor IA to- Y5A, .respectively, thereturn conductors IB to 5B, re-. spectively,4 the busy release wire, RBW, andthe call button Conductors IC to 5C, respectively, l`ead to the single control and amplifying station'shown inFig.2..1 W b .Referring to Fig.- 2, the controlfland amplifying station includes a pluralityof re1ays,MI, to M5,I respectively, connected to the soundwires-| IA to 5-A and button ,return wires IB Ito,,5B Sof-``the substation',, a plurality of relays-.SI to S5.- respectively, connected to the, call buttoncon'ductors I C` to ,'.iB,. anv amplifier AM, ,a -talk ylisten relay TL, a rectifier and filter RF, a busy .relay BR,andareleaserelayRR. .A Each of ,the`relays MI to Mi has avibratory movable contact A cooperating with fixedcon- `tactsc8 and 9, a vibratory or movable .contactfyB cooperatingwith a fixed contact IIl-I andV anlop- Each of the relays SI to S5 hasa vibratory or movable lcontact C cooperating with a fixedcon'j- ,t act I 2, ,a vibratory or-movable contact l:) f,.c```f .operating ..with a fixed contact I3, and anf'op; erating'coil I4. tThelnisyrelay BR ,has a vibratory or movable contact E ,cooperating with-.a .fixedv contact 45:,- .andan operating coil I6.. l The release relay-RR has a vibratoryor movi able contactv Fcooperating with a fixed grounded contact I'I,, an `dv an operating coil 18. A f 1." ii j The talk .listen relay' TI.. has anoperating coil |9, a vibratory or movable contactG cooperating with fixedcontacts v20 and 2 I, and a vibratorly or movablel-contact I- Icooperating with fixed con; tacts 22 and23. I IL; A conductor 24 connects the input side of the amplifiedAM lwith the contact G, anda conducf; tor 25 connects the output sidey ofsaid a .llflplifirI "The current supply wiresV 26 from any suitable sourceof alternating current connect .as shown with the rectifier andfilter RF, one of these lines 1991118 ,grounded Aand the Other,, connected by 11,06

ductor 21 'with one side of the coils IB, I8. The other side of the coil I 8 is connected by conductor 28 With the contact E. The other side of coil IG is connected by a vconductor 29 and branch ,conductors 29' to one side of the coils HI. The other side of each coil I 4 is connected to the contact D of its associated relay. M

The conductor RBW connectswith the fixed contact l5.

The contacts D of the relays SI .to S are also, respectively, connected to conductors IC to 5G.

The contacts 2| and 22 of the'talk -listen relay are connected to a common conductor 30 with Which the contacts C of the relays Sl to S5 are connected by branch .conductors 3,0'. Relay TL also has one side 'of its Icoil 119 .connected by @011% ductortl fwith branch 0.0.1.1ductors'32, .each conL nectedwith a-fixedflcomaols o jf renys sl toss.

VThe other fside of Vcoil lfllis'fconnectedby a conductor IV 33 Withb the contact FV of the release ,rtlayltlf't-4 V a Conductor 33 is also'eonnected to a common conductor 34 .tyhichfisfconnected by'branch conductors 35'to the fiired eontactsi,

One side ofwthe coils ll of relays MJ to MS iS 'connectedjby branchtconductors 35'. to a common "ground'conductoij ,36,1 ,and the other 'side of these .coi'l conneotr yotively, with the .button return -wires IB-to.5.B.` f

flfhfe gntactsgll and. Zt',.of'.'tne "talk .listen r e1ay arev connected to'acommonconductor 31 Vto Whichlthe. fiXed ontaots of thorelays MI to M5 are :connectedv'.''.I'.h`e ,contact of each M relay is, 'respecti ely, connected by a conductor `''st with .the 'fixoldjcontact L2, of .each S relay os Shown- The. sound wires lA'to 5A, respectively, connect with thefiontactsn for the .relays Mi to and the` button vreturn 'y'vires B ftoj '513, respectively, o'onriet with. t. e.. ionta'ctsjB of sam relays MI toM5.-` i

With t heabove described arrangement'if station 3`Wi$1is "30. talk liqfsfffifioni, the 02111. butliOIl (33.5 at,station. 3 is deurosserl 'and released'and 'any Sound. that enter'stheflouu speaker. at station 5 jati nowiv is acting l'as 1 a ..dynamic microphone Will be heard at the loudspea'k'er at'stat'ion 3, Tracing the ciruit from ,the DC inPfut fromf the'rectifier BF, the current iioiys through conductor 21, coil 'i "0.f'reloy`BB;foons111ot0r 71.9; conductor 29', and

coil 14 of'relay S5,`"'conductor 5C, button CBS ,of 19 I substation 3, button return Wire 3B,' c oil ll of relay and'itsconduetor 3 and conductor 36' tof'gifoilnd, .and'through ground'to the other supply cnndutor. `thus energi/ting coil' llto move .con-

tar-:t nida closed' position; with 'contest 15 sangat torrent mar thonoass from flonductor '21 through 'Coil "!`$;1.. =i. ln iu$t9rfii` to' busy. aiidrelese. wire RBW and through the' bus y l amns'l3ul .fin all the Subfitotions ..and .coedustOr-i 6' to! ground, but as tts's'e. Ia ps. 'take Deli' a; s.

vreleaserelay RB d @sngt 1 x pse, 'Coilll of relay .lafl'sibeing energized, `these relay,, areios'er'ated- .Contest BiofrelayMs then oonV ,.cts 'contat h .n contacts qnta't 1,3; .thertyallowing current tb pas's through coil .l Q'from 'conductors 34, 33 and 32,. 3 l and closing alocking circuit through coil [3, of'relay when' button 0,135 ofsubstation 3 iISfr-.el .afledfiinteurrent .thenffflowsfrom conductor`21, coi1`l6, conductor '23', ,coil lMof relay Salt,v contacts 1). and-13,,..condu'ctor 32, .conductor' 31,' 91911.19,lconductorsf33, 34,'V conductor 35,1and' contacts Hi ,and B of relay, M3, oi1 I l of said relay J.. c .iuotorafiif @tio .ground- V@torrent them passes through the coil [9 of the' relayTL whichl 11 amountbf current Sllllorlfcfl contatDlfof relay S5 rent is amplied and returns out through conductor 25 to contacts H and 23, conductor 31, contacts'19 and A of relay M3, sound Wire 3A, VC' of loud speaker at substation 3 to ground. Thus the momentary depression o f button CB5 at substation 3 Cells? .the .Operation of both .of the loud Speakers at'substations 3 and 5. f

To'talkffrorn ,substation 3 to substation 5 the cutton CB5 .at substation 3 is again pressed, and this causes a shortV circuit across the' coil I$ of 'the TL rem', Since' '92111, button CBfi .then acts to bridge the 'circuit including Conductors 34 and 3l, inverting the input and output of the ,andio amplifier AMcausing thesound Vto pass over the samepathas before but in the opposite direction so that the loud speaker at substation 3 then acts a s a r nicrophone'to transmit the message to the lou speaker at substation 5 then acting as a loud'speakeh The inyerting o f the input and output of the amplifier When coil IQ is deenergized takes place beagse oontactH moi/es from .Contaot 23 to oonf t act 23 and contact Ci moves from contact 2! to contat`20. .When the party ,at substationt initiating. the .call has 'finished orang. oe releases his call button 035, thus relieving the short front'coildllifof vthe talk-listen relay and again revrillg. amplifier AM Since contact .H then rnovcs into engagement With contact 23 and con.- tact G moves into engagement With contact Zl. Reversal of the AM then permits the called party at substation 5 Vto use the loud speaker at this 'station as a microphone and talk to sub- 'station 3 through the loud speaker at this station, since relay is .enere'ized and contact A isfin contact With contact. 9., Thus after the initial closing and release .Of call buttonCBto lOGkin relays M3 and S5 between substations and 5 conversation may be carried on, the button CB5 being closed While the party at substation 3 istalking and being released While the party at substati'on 5 is talking, but at no time does the .party at the called station have to operate any buttons o r levers. Upon termination of'the conversation over the speakers at substations 3 and 5 lthe calling party at' substation 3 depresses the release button RB at this station; This shorts thebusy lamp BL permitting coil |8 of relay RR tofipull up and move 'contact F into engagement With contact ll. This grounds relay M3 since contact vF is'connected by conductor 33 to conductor 34, branch conductor 35 of relay M3, contacts I!!v andV [3 of said relay and its coil ll connected to ground through conductor 36. l| of'relay MB being deenergized, contact B of saidrelay moves to openb position, thus opening thelocking circuit for the relay M3. With the opening of the relay M3 and separation of contatsi lu, and B thereof the circuit supplying coil M of relay S5 and including these contacts, conductor 35 for this` relay, lconductor 3 4,.coil 19, conductors 3l, 32, .contactsv l3 and D, coil M.,

conductor 29, .coil [6, and conductor 21 is openedl Coil is ready for another call. Only the substations that are talking with each other are active so that there is privacy between stations.

While I have shown the current Supply as AC current and a rectifier to provide DC for operating the relays, any suitable source of DCl current may be used.

For the purpose of claiming the invention the relays MI to M5 may be designated calling relays and the relays Sl to S5 receiving relays, it being noted that there are as many of each of these relays as there are substations and that while a five substation system has been shown, from two to any number of substations may be used.

It is to be further noted that while the call and release buttons are shown as push button switches or closures, any other suitable manually operated type of circuit closure may be used and that by the term call button and release button I mean a circuit closure of any suitable form. However, it is to be noted that the push button switches herein shown are not of the lock in type.

While on operation the busy relay BR closes putting voltage on the busy lamps BL through the coil |8 of the release relay RR, the lamps BL are of low wattage and do not draw enough current to cause the coil IB to close the release relay. Upon shorting the lamp BL by depressing the release button RB, the release relay coil |8 will then be energized to cut out the looking circuit as heretofore described.

The above described intercommunication system requires no master stations containing amplifiers at each master station but each substation can talk to any other substation, the talking being controlled by the party at the substation initiating the call.

I desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except in so far as such limitations are included in the claims.

What I claim as my invention is:

1. In an intercommunication system, the combination of a plurality of substations, each substation having a loud speaker with only one pair of Conductors carrying the voice currents therefore, a control button for every other substation controlling both the talking and listening with another substation and a release button, a source of current, an electronic amplifier a single talk listen relay having an operating coil and reversible switches controlled by said coil, circuit connections between said switches and said amplifier,l circuit connections between said switches, said loud speakers and said source of current including relay operated switches selectively controlled by said control buttons and connected in circuit with the operating coil of said talk listen relay, and means controlled by said release buttons for deenergizing the operating coil of said talk listen relay.

2. In an intercommunication system, the combination of a plurality of substations, each substation having a loud speaker with only one pair of conductors carrying the voice currents therefor, a control button for every other station and a release button, a source of current, an electronic amplifier, a single talk listen relay having reversible switches controlled thereby for connecting said amplifier with said source of current substations and said amplifier, said means being controlled by the operation of a control button at one substation for establishing current flow from said source to the loud speakers of the calling and called substations and rendering said talk listen relay operative to connect said amplifier to the loud speaker of the called substation when said button at the calling station is in closed circuit position and to connect said amplifier to the loud speaker of the calling station when said button at the calling station is in open circuit position, and means controlled by said release buttons for releasing said talk listen relay and the relays of said electrically controlled means.

3. In an intercommunication system, the combination of a plurality of substations, each substation having a loud speaker with only one pair of Conductors carrying the voice currents therefor, a control button forI every other substation and a release button, a source of current, an electronic amplifier, a single talk listen relay in circuit with said amplifier and said loud speakers having an operating coil and reversible switches controlled thereby for connecting said amplifier With said source of current and the loud speakers of the calling and called substations, circuit control means between said substations, said source and the loud speakers of the calling and called substations, electrically controlled means including relays connected with said control buttons for establishing the circuit connections between the loud speakers of the calling and called of current, amplifier and talk listen relay switches including two sets of relays, each relay of one set controlling a double throw switch having a movable contact and fixed contacts and a single throw switch, each relay of the other set controlling single throw switches, the movable memf' ber of each double throw switch being, respectively, electrically connected with one side of the loud speaker at one substation, one of the fixed contacts of each double throw switch being connected to one side of the talk listen relay switch, the single throw switch of the same relay electrically connecting one wire for a control button at one substation with the operating coil of the talk listen relay, one of the single throw switches of the other set of relays connecting said operating coil with the other Wire of said control button and with the source of current, the other of said single throw switches of said other set of relays being connected to the other fixed contact of the double throw switch of the first named set and to the other side of the switch of said talk listen relay, the operation of a control button at calling substation acting to establish a talk-listen circuit with the desired called station through said talk-listen relay, amplifier and the loud speakers of the called and calling substations, further operation of said control button selectively controlling the output of said amplifier to either of the loud speakers of said called and calling substations.

WTLLIAM E. WADSWORTH.

BEFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,146,362 Thomsen Feb. '7, 1939 2,162,369 Campbell June 13, 1939 2,249,456 Campbell July 15, 1941 2,269,141 Campbell Jan. 6, 1942 FOREIGN PATENTS Number Country Date 223,981 Great Britain Oct. 31, 1924 

